Manufacture of nitrocellulose-and-casein compounds.



' UNITED STATES PATENT OF ICE CHARLES BEBNADAVO,

oF PARIs, FRANCE. I

MANUFACTURE OF NITROC ELLULOSE-AND-CASElN COMPOUNDS. i

V SPECIFICATION forming part of Letters Patent No. 700,4713dated Me't'y20, 1902:

Application filed February 4, 1902.

To all whom it may concern 7 1 Be it known that I, CHARLES BERNADAO, a citizen of the French Republic, residing in ,Paris, France, have invented-certain new and and known as lactite, lactoid," and gallolithe.

Notwithstanding'the improvements in the manufacture, the cost'price of celluloid is still very high, and this is thegreatest obstacle to I process'to manufacture a perfectly homoge v its more general use." Thus, for example, it

is easy to produce a celluloid in perfect imitation of bone and horng'butthe price is too high and does not admit of its being'used in place of natural products. The products with casein base can be manufactured cheaper than those with nitrocellulose base;'but as they arealways more or less-liableto break and become more so with age their use, is rather limited.

After numerous experiments I havesucceeded' in the manufacture of a new material having a base of casein and nitrocellulose at a much lower cost price than celluloid, which latter it can replace in all its applications because it has the same qualities. It is flexible, very hard without being brittle, impermeable to water. It may be sawed, turned, filed, and carved without difficulty. At a temperature of 90 to 100 centigrade it becomesvery plastie and can be molded with ease. If pure casein is employed for manufacturing the new compound, the final product will be transparent, with a slightly cream-colored appearance. With non-purified casein a translucent productis obtained, which may be colored at will by an addition of coloring-matter either of organic or a mineral nature, and in this manner horn, coral, bone, 850., can be easily imitated.

At firsts'ight the manufacture of a compound with a nitrocelluloseand-casein base would not seem to present any difficulties; but as the solvents of casein are incapable of Serial No.92,7l2. (No specimens.) I

dered plastic by the addition of one of its solvents (a solution of camphor in'alohol," for If, for example, an attempt is made example) With casein, the final product will" be found to be far from-homogeneous; not

withstanding a prolonged kneading operation in rollers or other mixing apparatus.

This final'product is an-imperfect mixture of casein and celluloid. Each grainof casein, although embedded in a cover of celluloid, remains'per meable to water,"and'the compound thus ob-' tained is found unfit'for industrial purposes. I have been ableby employing the following .neous material'of which the composition may vary from one hundred to three hundred parts ,of'casein to onehu'ndred'parts of nitrocellulose and of-which the manufacturingwprice .will bemore or lessnearefthatofj products ofcasein base, according to the proportions of nitrocellulose and cas'ein'introduced. j

To obtain a perfect nitrocellulose-and ca sein mixture, these two substances are first rendered plastic, as before mentioned, the nitrocellulose being, as in the manufacture of celluloid, treated with a solution of camphor in alcohol. lulose forty to sixty kilos of camphor in alcohol of 95 to 96 may be employed.

For casein two different methods may be adopted. I

(a) Casein is immersed for twenty four to twenty-eight hours in a solution of borax in water, (one to five kilos of borax in one hundred kilos of water.) Instead of borax car bonate of soda or any other substance capa-.

ble of dissolving casein may be employed. During the immersionthe casein swells and becomes plastic and at the end of twentyfour to twenty-eight hours the mass is dried and then plunged in alcohol, which displaces part of the water absorbed by the casein, while nevertheless leaving it in its physical state.- Instead of alcohol either methylic alcohol, acetone, sulfuric ether, or acetic acid maybe employed, or, indeed, any other liquid or mixture of liquids capable of'dissolvi For one hundred kilos of nitrocel- V nitrocellulose. After immersion for several hours the excess of the liquid is separated from the mass of casein by pressing or in some other appropriate manner, and this mass is then ready to be incorporated in the mass of nitrocellulose prepared in the manner previously stated.

(1)) Another method of operating for forming the casein into a plastic mass is as follows: A solution of borax or another substance acting as a solvent for the casein is added in part to a solution of three to ten parts of alcohol or other liquid capable of dis solving the nitrocellulose. In theliquid mixture the casein is immersed for twenty-four or twenty-eight hours, as previously stated, and is then pressed and dried.

when treating casein freshly precipitated from the milk, the proced ure will be, as stated in paragraph Z), by taking care to dry the casein before immersing it in the liquid, as before described.

The two substances, casein and nitrocellulose, thus prepared can now be easily mixed together in rollers and kneaders or apparatus of a similar kind. I prefer generally to employ laminating-rollers for this work. Laminating rollers or cylinders adapted to be heated and cooled similar to those employed in the manufacture of celluloid will be found very convenient for the treatment of the mixture. This operation may be carried out in various manners. For example, the plastic mass of nitrocellulose is charged into a laminating-roller and after having been treated for thirty to forty minutes the casein is incorporated little by little, or the casein mass may be placed first in the laminating-roller, and after it has become nearly homogeneous the nitrocellulose mass is added to it. It desired, however, the two substances may be simultaneously placed in the laminator, or they may each be separately worked for a certain time and then mixed together in a third laminator. All three methods give good results. The plastic mass of casein saturated with alcohol or other solvent of nitrocellulose mixes in this condition in a perfect manner with the nitrocellulose mass and the mass becomes perfectly homogeneous after having been treated for a certain time. As the cylinders of the laminator are heated the mass becomes gradually more and more consistent, as the solvents evaporate, and after a treatment varying from three to four hours a transparent or translucent homogenous mass is formed. This mass is laminated in sheets of five to ten millimeters thickness, and a certain number of sheets are compressed while heated in a hydraulic press similar to those employed in the manufacture of celluloid. Thesesheets adhere together and form a block, which is then cut into pieces of the required thickness in the manner usually adopted in the manufacture of celluloid. Coloring-matter,whether mineral or organic, may be readily incorporated with the mass during the treatment in the laminating-rollers, and this permits of obtaining all the tints and any mixtures of tints it may be desired to produce.

The proportions of nitrocellulose and casein may vary according to the results to be obtained, the quality, and cost price of manfacture. Thus a mixture of one hundred parts of casein to two hundred of nitrocellulose will give a product entirely equivalent to ordinary celluloid. A mixture of one hundred parts of casein to one hundred of nitrocellulose gives a slightly-yellow product, but having all the qualities of ordinary celluloid and being cheaper. Lastly, if it is desired to obtain a very cheap product twohundred to three hundred parts of casein may be mixed with one hundred of nitrocellulose and this mixture gives a product adapted to replace ordinary celluloid in most ofits applications and at a much lower cost of manufacture.

The celluloid em ployed in my improved process may be ordinary celluloid prepared with camphor.

Having thus described my invention, I claim 1. The herein-described process ofproducingahomogeneous compound of nitrocellulose and casein, which consists in forming a plastic mass of the casein in one of its solvents, the latter being an aqueous solution, replacing the water, in part, from the said plastic mass with a liquid solvent of nitrocellulose, then removing the excess of liquid from the plastic mass, and finally incorporating with the mass of casein a mass of plastic nitrocellulose and kneading the same to form a homogeneous compound.

2. The herein-described method of producing ahomogeneous compound of nitrocellulose and casein, which consists in to wing a plastic mass of the casein with an aqueous solution of borax, then removing the surplus Water, then immersing the mass in alcohol to displace a part of the water-absorbed by the casein, then removing the excess of liquid from the mass, then incorporating the mass of casein thus prepared with a mass of plastic nitrocellulose and kneading the whole into a homogeneous compound.

3. The homogeneous compound of nitrocellulose and prepared casein above described.

In witness whereof I have hereunto signed my name, this Blth day of January, 1902, in the presence of two subscribing witnesses.

CHARLES BERNADAC.

Witnesses:

MARUL ARMENGAUD, EDWARD P. MACLEAN. 

